1 files changed, 11 insertions, 0 deletions
diff --git a/lib/rubygems/requirement.rb b/lib/rubygems/requirement.rb
index bcf5fb967e..572bf9673e 100644
--- a/lib/rubygems/requirement.rb
+++ b/lib/rubygems/requirement.rb
@@ -23,6 +23,8 @@ class Gem::Requirement
     "~>" =>  lambda { |v, r| v >= r && v.release < r.bump }
   }
 
+  SOURCE_SET_REQUIREMENT = Struct.new(:for_lockfile).new "!" # :nodoc:
+
   quoted  = OPS.keys.map { |k| Regexp.quote k }.join "|"
   PATTERN_RAW = "\\s*(#{quoted})?\\s*(#{Gem::Version::VERSION_PATTERN})\\s*" # :nodoc:
 
@@ -54,6 +56,8 @@ class Gem::Requirement
       input
     when Gem::Version, Array then
       new input
+    when '!' then
+      source_set
     else
       if input.respond_to? :to_str then
         new [input.to_str]
@@ -70,6 +74,13 @@ class Gem::Requirement
     new '>= 0'
   end
 
+  ###
+  # A source set requirement, used for Gemfiles and lockfiles
+
+  def self.source_set # :nodoc:
+    SOURCE_SET_REQUIREMENT
+  end
+
   ##
   # Parse +obj+, returning an <tt>[op, version]</tt> pair. +obj+ can
   # be a String or a Gem::Version.